Local firm allegedly sold more than 250,000 doses that failed to meet safety standards

HONG KONG—Chinese Premier Li Keqiang called for a government investigation into “the entire process chain of all vaccine production and sales,” after a drug company allegedly sold more than 250,000 doses that failed to meet safety standards.

Shares of major local vaccine makers, including a Merck & Co. partner, tumbled Monday after Mr. Li’s statement was released a day earlier. He didn’t elaborate on what more his government would do to investigate.